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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

18515 results found.

  1. GRB 110820A: Swift/UVOT Upper Limits
  2. GRB110820A: MITSuME Ishigakijima Optical Upper Limits
  3. GRB 110820A: Enhanced Swift-XRT position
  4. GRB 110820A: CrAO optical upper limit
  5. GRB 110820A: Swift detection of a burst
  6. GRB 110818A: Swift/UVOT Upper Limits
  7. GRB 110818A: Enhanced Swift-XRT position
  8. GRB 110818A: Optical afterglow and redshift from VLT/X-shooter
  9. GRB 110818A: Swift-XRT refined Analysis
  10. GRB 110815A: Swift-XRT and UVOT refined Analysis
  11. GRB 110818A: Swift detection of a burst
  12. GRB 110801A: optical observations at Mt. Terskol observatory
  13. RXTE Discovery of the Spin Period of Swift J1834.9-0846
  14. Fermi Gamma-ray Burst Monitor trigger 110809.346 is not a GRB
  15. GRB 110808A: Swift/UVOT Detection
  16. GRB 110808A: Swift-XRT refined Analysis
  17. GRB 110808A: Enhanced Swift-XRT position
  18. GRB 110808A: Swift detection of a burst with optical counterpart
  19. GRB 110807A: SAO RAS observations
  20. GRB 110807A: Swift detection of a burst or a posible new SGR
  21. GRB 110726A: two epochs of SAO RAS optical observations
  22. IPN triangulation of GRB110802A (short/hard burst)
  23. GRB 110801A: optical observations in CrAO
  24. EVLA observation for Fermi burst GRB 110721A
  25. GRB 110801A: SAO RAS optical observations
  26. GRB110801A: MITSuME Ishigakijima Optical Observation at 1 day after the burst
  27. Swift/UVOT observations of GRB110801A
  28. GRB110801A: MITSuME Ishigakijima Optical Observation
  29. GRB 110801A: Enhanced Swift-XRT position
  30. GRB 110801A: Swift detection of a burst with an optical counterpart
  31. GRB110731A: MITSuME Ishigakijima Optical Upper Limits
  32. GRB110731A: Swift/UVOT Observations
  33. GRB 110731A: NOT photometry
  34. GRB 110731A: Enhanced Swift-XRT position
  35. GRB 110731A: Swift detection of a burst with an optical counterpart
  36. INTEGRAL Weak trigger #6331: GRT Optical Observation
  37. GRB 110721A: Swift observations of afterglow candidate
  38. GRB 110726A: optical upper limit in CrAO
  39. Swift detection of a SGR-like burst from the AXP 4U 0142+61
  40. GRB110726A: MITSuME Ishigakijima Optical Observation
  41. GRB 110726A: Further Swift/UVOT Observations
  42. GRB110726A: Gemini-N tentative redshift
  43. GRB 110726A: Enhanced Swift-XRT position
  44. GRB 110726A: Swift/UVOT Detection
  45. GRB 110726A: Swift detection of a burst
  46. IPN triangulation of GRB 110721A
  47. GRB 110721A: Preliminary Swift/UVOT Upper Limits
  48. GRB 110721A: potential counterpart candidate
  49. GRB 110719A: GRT Optical Observation
  50. GRB 110719A: optical limit by "Pi of the Sky"
  51. GRB 110719A: z-band upper limit
  52. Swift/UVOT observations of GRB110719A
  53. GRB 110719A: optical upper limit
  54. GRB 110719A: Enhanced Swift-XRT position
  55. GRB 110719A: Swift detection of a burst
  56. Swift J1822.3-1606: Transient Magnetar or Be X-ray Binary?
  57. GRB110715A: GROND Detection of the Optical/NIR Afterglow
  58. GRB 110715A: APEX detection of the submm counterpart
  59. GRB 110715A: Swift/UVOT Detection
  60. GRB 110715A: Enhanced Swift-XRT position
  61. Swift J1822.3-1606: A Probable New SGR in Ground Analysis of BAT Data
  62. GRB 110715A: Swift detection of a bright burst with an optical counterpart
  63. GRB 110709B: Swift/UVOT Observations
  64. Swift trigger 457076 is not a GRB
  65. GRB 110709B: Submm observations from APEX
  66. IPN triangulation of GRB 110708B (long duration, extremely intense)
  67. Swift Trigger 457076: a possible GRB
  68. GRB 110709A: Swift/UVOT Upper Limits
  69. GRB 110709A: Konkoly observations
  70. GRB 110708A: Konkoly observations
  71. GRB 110709B BAT refined analysis
  72. GRB 110709B: Swift-XRT refined Analysis
  73. GRB 110709B: Swift/UVOT Detection of Possible Optical Flaring
  74. GRB110709A: MITSuME Ishigakijima Optical upper limits
  75. GRB 110709B: Enhanced Swift-XRT position
  76. GRB 110709B: GROND Detection of an Afterglow Candidate
  77. GRB 110709B: Gemini-South optical observations
  78. GRB 110709A: Enhanced Swift-XRT position
  79. GRB 110709B: Swift detection of a burst
  80. GRB 110708A: Swift/UVOT Observations
  81. GRB 110709A: Swift detection of a burst
  82. GRB 110708A: Swift/XRT afterglow candidate for the INTEGRAL burst
  83. IPN triangulation of short hard GRB 110705A
  84. Swift trigger 456780 is not a burst
  85. Swift Trigger 456659 is probably not astrophysical
  86. Swift-BAT trigger 456532 is not astrophysical
  87. SGR 1E 1841-045: early optical limit by "Pi of the Sky"
  88. SGR 1E 1841-045: Swift detection of a soft gamma repeater burst
  89. Swift J185003.2-005627: 1.23m CAHA and BOOTES-3 observations
  90. GRB 110625A: Fermi GBM and LAT observations
  91. GRB 110625A: Swift/UVOT Upper Limits
  92. GRB 110625A: 1.23m CAHA I-band observations
  93. GRB 110625A: Fermi LAT detection
  94. GRB 110625A: GROND detection of a source inside the XRT error circle
  95. GRB 110625A: Konkoly observations
  96. GRB 110625A: Swift-XRT refined Analysis
  97. Swift J185003.2-005627: NIR Observation
  98. GRB 110625A: Swift detection of a burst
  99. Swift J185003.2-005627: Swift-XRT/UVOT refined analysis
  100. Swift J185003.2-005627: TAROT La Silla observatory optical observations

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